WO2006008178A1

WO2006008178A1 - Ink cartridge for an ink-jet printing system, seal joint for said ink cartridge and method for the production thereof

Info

Publication number: WO2006008178A1
Application number: PCT/EP2005/008027
Authority: WO
Inventors: Reinhard Maier; Mathias Nagl
Original assignee: Kmp Printtechnik Ag
Priority date: 2004-07-22
Filing date: 2005-07-22
Publication date: 2006-01-26
Also published as: DE102004035573A1; EP1771303A1

Abstract

The invention relates to an ink cartridge (7) comprising a supply connection (1) for ink filling and/or emptying and a seal joint (3) for sealing the ink cartridge (7) against the ink outflow through said supply connection (1), wherein the supply connection (1) is provided with a reception area (2) for the seal joint (3), said seal joint (3) is provided with an opening (4) and has an internal pressure which is equal to or greater than 10 mbar, at least 100 mbar, preferably 1 bar, thereby making it possible to press the opening (4) against the joint in such a way that it is sealed and/or the seal joint (3) is pressed against the opening (4) through the reception area (2) in such a way that the opening (4) is sealed. The seal joint (3) and a method for producing said cartridge (7) are also disclosed. Said invention is characterised in that it makes possible to attain a high robustness and sealing capacity of the cartridge (7) even when a truncated needle is applied to the ink jet printer, a movement path of the needle is short and even when the multiple assemblies and disassembles of the cartridge are carried out.

Description

Ink cartridge for an inkjet printing system, seal for an ink cartridge and method for producing the same

The present invention relates to an ink cartridge for an inkjet printing system, comprising a supply connection for filling and / or removing ink and a seal for sealing the ink cartridge against leakage of ink at the supply connection, the supply connection being a receptacle for the seal has and the seal has an opening; a seal for an ink cartridge and a method for the manufacture of such an ink cartridge.

Ink is usually supplied to inkjet printers via a hollow needle and a tubular, protruding mandrel, a fluid-conducting connection being established between the printer and an ink-filled, replaceable, disposable ink cartridge serving as a storage container. To accommodate a dome, a tube section, the so-called dome, is generally formed in the ink cartridge, which is closed at its inward opening with a fine-meshed filter screen and at its outer opening with sealing means for sealingly receiving the aforementioned hollow needles , of the cathedral.

Alternatively, solutions are described in the prior art, for example in US Pat. No. 5,790,158, in which an annular seal with a preformed opening for receiving the hollow needle or an initially closed membrane which can be pierced by the hollow needle is used. An advantage of using pierceable membranes is that the removal opening is air-tight. is tightly closed without first requiring additional packaging and securing measures. The disadvantage here, however, is that a secure seal cannot always be guaranteed, in particular in the event that comparatively blunt needles are used to avoid injuries. DE 199 43 947 A1 proposes to use membranes which have a reduced elongation at break due to the addition of inelastic, inorganic substances, as a result of which a comparatively secure seal can be achieved even with the use of relatively blunt needles with a short movement path available . A disadvantage of such solutions, however, is that if the ink cartridge is installed and removed several times in or out of the inkjet printer, it is not always possible to ensure a satisfactory sealing capacity due to the multiple perforations in the seal.

It is therefore an object of the present invention to provide an ink cartridge, a method for producing an ink cartridge for an inkjet printing system and a seal, with which a secure seal against leakage of ink even when using a relatively blunt needle during a cure ¬ zen available movement path can be guaranteed even with repeated installation and removal of the ink cartridge.

This object is achieved according to the invention by the ink cartridge, the method for producing the ink cartridge or the seal as specified in the independent claims. Advantageous refinements and developments, each of which can be used individually or combined with one another as desired, are the subject of the respective dependent claims. The ink cartridge for an ink jet printing system according to the invention comprises a supply connection for the ink supply and / or removal and a seal for sealing the ink cartridge against leakage of ink at the supply connection, the supply connection having a receptacle for the seal and the seal having an opening, wherein the Sealing has an internal pressure of at least 10 mbar, in particular of at least 100 mbar, preferably of at least 1 bar, by means of which the opening is compressed, in particular sealed.

With the aid of the supply connection, the ink cartridge can be filled with ink and / or ink can be supplied from the ink cartridge to the inkjet printing system. With the aid of the supply connection, the ink cartridge can be connected, for example, to the inkjet printing system. There is usually a corresponding hollow needle on the inkjet printing system, which can be inserted into the interior of the dome on the ink cartridge and is sealed with the aid of the seal. Conversely, however, solutions are also conceivable in which the ink cartridge has such a hollow needle and engages in a corresponding dome on the ink jet printing system. The supply connection has a receptacle into which the seal can be inserted.

Internal pressure means the pressure inside the seal, which can be measured, for example, by a miniaturized pressure sensor inside the seal. With the help of the inner pressure in the seal, a sealing ability of the seal is ensured even when the ink cartridge is installed and removed several times. The sealing effect is achieved in particular when the ink cartridge is not inserted into the printer and, in particular, no hollow needle passes through the opening. Especially with multiple penetration of the Sealing through the hollow needle ensures the necessary pressure for the internal pressure. The internal pressure can be measured, for example, by providing the seal with a small slot into which two capacitor plates which are spaced apart by means of a gas cushion are introduced, the pressure being determinable via the capacitance of the capacitor.

Alternatively or also in connection with the internal pressure described above, the ink cartridge according to the invention for a ink jet printing system comprises a supply connection for filling and / or removing ink and a seal for sealing the ink cartridge against leakage of ink at the supply connection, the supply connection having a receptacle for the seal and the seal has an opening, the seal being compressed by the receptacle, as a result of which the opening is compressed, in particular sealed.

The compression of the seal with the aid of the receptacle ensures a seal even when the ink cartridge is installed and removed several times in or out of the inkjet printer. The sealing effect is achieved in particular when the ink cartridge is not inserted in the printer. Compression takes place through a correspondingly different shape of the seal and its reception. For example, the cross section of the receptacle into which the seal is inserted is smaller than the cross section of the seal. It can also be expedient to provide a projection in the receptacle through which the seal is compressed or compressed. With the help of the compression or with the help of the internal pressure, the seal can achieve a sealing effect even if it already has a perforation. The perforation is compressed and sealed by the internal pressure or compression. The internal pressure or the compression is advantageously anisotropic. Anisotropic in this context means that the internal pressure or compression is stronger in one direction than in another. In particular, this means a rotationally asymmetrical internal pressure or compression. For example, the internal pressure or the compression in one direction within the opening level of the supply connection is negligible and is sufficiently high in a direction perpendicular to this in order to achieve a sealing effect.

The internal pressure or the compression acts advantageously within an opening level of the supply connection. However, it is also possible that squeezing the seal in a direction perpendicular to the opening plane of the supply connection causes a compression or an internal pressure within the opening plane, whereby a sealing effect can be achieved. The seal advantageously has an opening, in particular an elongated opening, preferably a slot. This opening ensures reproducible opening and closing of the seal even when comparatively blunt needles are used. As soon as the seal comes into engagement with the blunt hollow needle, it opens at its opening and, due to the internal pressure or the compression, establishes a tight connection between the ink cartridge and the inkjet printing system.

The direction of the internal pressure or the compression is advantageously transverse, preferably perpendicular, to the longitudinal direction of the opening, in particular the opening is compressed by the internal pressure or the compression. With such an arrangement of the longitudinal direction of the opening relative to the compression or the internal pressure, it is ensured that the opening is securely sealed against leakage of ink. It is advantageous if the seal and / or the receptacle is rotationally unsymmetrical, in particular oval or rectangular. A certain discrepancy between the outer contour of the seal and the inner contour of the receptacle is advantageous for compression. For example, an oval-shaped seal is pressed into a circular-shaped receptacle or, conversely, a seal with a circular cross-section is pressed into a non-circular (for example oval) shaped receptacle. It is also conceivable to insert a square seal in a somewhat smaller, rectangular receptacle, which compresses the seal in one direction. In such solutions, compression of the seal is caused by a contour incompatibility of the seal and the receptacle.

As an alternative to this contour incompatibility, sealing can also be achieved by intrinsic tension. For example, the seal is clamped by a snap action: the seal is produced in a first state in which the seal is relaxed accordingly, ie without internal pressure or compression; the seal is then deformed such that the seal snaps into a mechanically quasi-meta-stable state. In this way, the seal remains in a stable state, which, however, due to the deformation causes a pressure inside the seal or an internal compression of the seal. By suitable shaping of the seal and with the aid of a corresponding deformation, a tensioned state of the seal can thus be achieved, in which the seal is mechanically stable but tensioned in such a way that a sealing effect is achieved even without further external application of force. While the relaxed state corresponds to the absolute minimum in the potential for elastic deformation of the seal, the metastable state represents only a local secondary minimum. With the help of this internal tension or the internal pressure, a sealing effect can be achieved can be achieved even with repeated installation and removal of the ink cartridge from the inkjet printing system.

The seal is advantageously formed by a membrane. With the help of this membrane, the supply connection is sealed over its opening level.

The seal expediently has an elastomer, in particular a thermoplastic elastomer. Due to the flexible property of the seal, an opening in it is always sealed off due to the compression or the internal pressure.

While the sealing system described can in principle be used both for filling and for removing ink, it is particularly suitable, in particular, for removing ink from the ink cartridge, since here special requirements are placed on the robustness of the seal, in particular also for repeated installation and removal of the ink cartridge in and out of the printer.

In the method according to the invention for producing an ink cartridge for an inkjet printing system, the ink cartridge comprising a supply connection for filling and / or removing ink and a seal for sealing the ink cartridge against leakage of ink at the supply connection, the supply connection has a receptacle for the seal and the seal has an opening, an internal pressure of at least 10 mbar, in particular of at least 100 mbar, preferably of at least 1 bar, is impressed on the seal, by means of which the opening is compressed, in particular sealed, and / or the seal when put in the receptacle upset by the receptacle, so that the opening is compressed, in particular sealed.

By introducing an internal pressure into the seal or compressing the seal, leaks of the ink cartridge are avoided both when the ink cartridge is inserted and when it is removed. The internal pressure or the compression can be effected with the aid of the receptacle, in particular a difference between the shape of the seal and the shape of the receptacle, preferably the inner contour of the receptacle and the outer contour of the seal. The internal pressure or the compression can, however, also be induced by a corresponding shaping of the seal and a corresponding deformation of the seal, in that the seal experiences a potential minimum due to the shaping in the deformed state, as a result of which a mechanically metastable state of the seal is achieved, in which the seal remains stable with a certain tension or an internal pressure. Here, the seal is manufactured in a mechanically relaxed first state in such a way that it can be deformed into a mechanically clamped second state in which it can remain stable; the seal is then transferred from the first to the second state by elastic deformation.

The internal pressure or the compression is advantageously anisotropic, as a result of which, in particular, large, elongated openings can be securely closed and sealed against leakage of ink.

The seal according to the invention, in particular for an ink cartridge of an ink pressure system with an opening, provides that the seal has an internal pressure of at least 10 mbar, in particular of at least 100 mbar, preferably of at least 1 bar, by means of which squeezed the opening, especially sealed. The internal pressure or the compression in the seal is advantageously anisotropic. The seal can in particular be deformed with a snap effect from a first deformation state into a second deformation state.

Further particular embodiments and advantages of the invention are explained further with reference to the following drawing, which is not intended to restrict the invention but merely to illustrate it by way of example. The following schematically show:

1 shows a perspective oblique view of a seal used in the ink cartridge according to the invention;

FIG. 2 shows the seal according to FIG. 1 in a perspective cross section;

3 shows a detail of an ink cartridge according to the invention with a dome;

Figure 4 shows the seal of Figures 1 and 2 in plan view.

5 a shows a seal in a relaxed state for a further ink cartridge according to the invention in cross section; and

Fig. 5b, the seal according to Fig. 5a in a clamped state. 3 shows a section of an ink cartridge 7 according to the invention, which has a receptacle 2 on a supply connection 1, which is designed as a dome 9. When the seal 3 shown in FIG. 1 is inserted into the receptacle 2, the oval seal 3 becomes due to the essentially circular receptacle 2 compressed along the longitudinal direction of the oval, whereby the opening 4, which is designed as a slot 5, is compressed and sealed. Fig. 1 shows the seal 3 in the form of a membrane 6, which has an opening 4 through which a hollow needle (not shown) of an ink jet printing system (not shown) can penetrate. The opening 4 is formed as an elongated slot 5, which is compressed after the seal 3 has been inserted into a receptacle 2 (see FIG. 3) and the resulting compression. Fig. 2 shows the seal 3 of FIG. 1 in cross section.

4 shows the seal 3 in plan view and the force F required for closing the opening 4.

5a and 5b show a further embodiment of the seal 3 for an ink cartridge 7 according to the invention, in which compression or internal pressure is not built up with the aid of a receptacle 2, but is intrinsically effected by the seal 3 itself. For this purpose, the seal 3 is made of an elastomer, in particular a thermoplastic elastomer, as can be seen, for example, from FIG. 5a. In this state, the seal 3 is in a completely relaxed state. The seal 3 is then folded over in a direction R, as a result of which a compression pressure P arises in an inner region of the seal 3. By folding over, the seal 3 snaps from a first deformation state into a second deformation state. Both the first and the second state of deformation can be mechanically stable. The compression pressure causes an internal pressure or a compression in this area. With the aid of a stabilizing means 8, which is configured here as a bulge on the seal, the membrane 3 is stabilized in the folded state, so that the seal 3 in the tensioned state, shown in FIG. 5b, does not in the relaxed state by itself according to Fig. 5a can fold back. The shape of the seal or of the stabilizing agent is measured such that penetration of a hollow needle of an inkjet printing system (not shown) cannot cause the membrane to fold back. The compression pressure P effects a sealing effect in an inner region 10 of the membrane 3. In this sealing variant, the sealing is effected by means of a compression that is inherent in the seal or a resulting internal pressure, in particular by means of a special shape of the seal and a subsequent deformation of the seal. This can lead, for example, to a configuration of the seal in such a way that the seal itself, for example, is relaxed when the needle is inserted, but tensions in the specified manner when the needle is pulled out, and thus seals the ink cartridge at the ink outlet from the environment becomes.

The invention relates to an ink cartridge 7 for an ink jet printing system, comprising a supply connection 1 for filling and / or removing ink and a seal 3 for sealing the ink cartridge 7 against leakage of ink at the supply connection 1, the supply connection 1 having a receptacle 2 for the seal 3 and wherein the seal 3 has an internal pressure of at least 10 mbar, in particular at least 100 mbar, preferably at least 1 bar, and / or the seal 3 is compressed by the receptacle 2; as well as a seal 3 and a method for producing such an ink cartridge 7. The invention is characterized in that a particularly tight connection between the ink cartridge 7 and an ink jet printing system can be produced, which makes the ink cartridge extremely robust and sealable even when used with a dullness Needles and a short path of movement of the needle guaranteed even with repeated installation and removal of the ink cartridge 7. Reference numerals

1 supply connection 2 receptacle

3 seal

4 opening

5 slot

6 membrane 7 ink cartridge

8 stabilizing agents

9 dom

10 inner area

Claims

1. ink cartridge (7) for an inkjet printing system comprising a supply connection (1) for filling and / or removing ink and a seal (3) for sealing the ink cartridge (7) against leakage of ink at the supply connection (1) , wherein the supply connection (1) has a receptacle (2) for the seal (3) and the seal (3) has an opening (4), characterized in that the seal (3) has an anisotropic internal pressure of at least 10 mbar, in particular of at least 100 mbar, preferably of at least 1 bar, through which the opening (4) is compressed, in particular sealed.

2. Ink cartridge (7) for an ink jet printing system, comprising a supply connection (1) for filling and / or removing ink and a seal (3) for sealing the ink cartridge (7) against leakage of ink at the supply connection (1) , wherein the supply connection (1) has a receptacle (2) for the seal (3) and the seal (3) has an opening (4),

characterized in that the seal (3) is compressed by the receptacle (2), as a result of which the opening (4) is compressed, in particular sealed.

3. Ink cartridge (7) according to claim 1 or 2, characterized in that the internal pressure or the compression is anisotropic.

4. Ink cartridge (7) according to any one of claims 1 to 3, characterized gekenn¬ characterized in that the opening (4) is elongated, in particular a slot (5).

5. Ink cartridge (7) according to claim 3, characterized in that the direction of the internal pressure or the compression is transverse, preferably perpendicular, to the longitudinal direction of the opening (4), in particular the opening (4) by the internal pressure or Compression is compressed.

6. ink cartridge (7) according to any one of the preceding claims, characterized ge indicates that the seal (3) and / or the receptacle (2) is rotationally asymmetrical, in particular oval or rectangular.

7. ink cartridge (7) according to any one of the preceding claims, characterized in that the seal (3) is clamped by snapping.

8. ink cartridge (7) according to any one of the preceding claims, characterized ge indicates that the seal (3) is formed by a membrane (6).

9. ink cartridge (7) according to any one of the preceding claims, characterized ge indicates that the seal (3) has an elastomer, in particular a thermoplastic elastomer.

10. ink cartridge (7) according to any one of the preceding claims, characterized ge indicates that the supply connection (1) is only suitable for removing ink.

11. A method for producing an ink cartridge (7) for an inkjet printing system, the ink cartridge (7) having a supply connection (1) for filling and / or removing ink and a seal (3) for sealing the ink cartridge (7) against leakage of ink at the supply connection (1), the supply connection (1) having a receptacle (2) for the seal (3) and the seal (3) one

Has opening (4), characterized in that the seal (3) is impressed with an internal pressure of at least 10 mbar, in particular at least 100 mbar, preferably at least 1 bar, through which the opening (4) is compressed, in particular the latter is sealed, and / or the seal (3) is compressed by the receptacle (2) when it is inserted into the receptacle (2), so that the opening (3) is compressed, in particular sealed.

12. The method of claim 11, wherein the internal pressure or the compression is anisotropic.

13. Seal (3), in particular for an ink cartridge (7) of an ink printing system, with an opening (4), the seal (3) having an internal pressure of at least 10 mbar, in particular of at least 100 mbar, preferably at least 1 bar, through which the opening (4) is compressed, in particular sealed.

14. Seal (3) according to claim 13, wherein it is anisotropic internal pressure or the compression.

15. Seal (3) according to claim 13 or 14, characterized in that the seal can be deformed with a snap effect from a first deformation state to a second deformation state.